Herein, we discuss the recent advances in boosting the electrochemical performance of LNMO. Further research directions of LNMO are also discussed, such as machine learning and AI-assisted virtual experiments, providing new insight for the development of LNMO cathodes.

Constructing an interlinked three-dimensional conductive carbon structure as a sulfur host is considered to be an effective strategy for suppressing the capacity decay over long-term cycling and improving the rate performance of lithium–sulfur (Li–S) batteries, because it can not only facilitate rapid electronic and ionic transportation in the cathode, but also be conducive to confine lithium polysulfide (LiPS) dissolution and shuttling. In this report, we designed a novel 3D conductive network structure (CNTs/Co–NC), which is composed of Co–NC (cobalt embedded in an N-doped porous carbon composite) derived from ZIF-67 polyhedra and inserted carbon nanotubes (CNTs), and applied it as a sulfur host for Li–S batteries. The CNT/Co–NC network structure is firstly prepared via the in situ nucleation of small ZIF-67 crystals on the surface of CNTs and eventually grown into CNT/ZIF-67 hybrid materials; after subsequent carbonization and infiltration of sulfur procedures, the S@CNT/Co–NC cathode is obtained. Li–S batteries based on the S@CNT/Co–NC cathode show an improved rate capability of 772.6 mA h g⁻¹ at the 2 C rate, enhanced long cycling stability under a large current density with a low capacity decay rate of ∼0.067% per cycle at the 0.5 C rate after 500 cycles and ∼0.072% per cycle at the 1 C rate after 700 cycles and an excellent coulombic efficiency of about 95% up to 500 cycles at 0.5 C and 91% up to 700 cycles at 1 C. The superior performance of S@CNTs/Co–NC should be ascribed to the rapid charge transfer, excellent electron conductivity, improved adsorption capability for LiPSs and enhanced redox kinetics of this 3D conductive network structure.

Cobalt-free spinel LiNi_0.5Mn_1.5O₄ (LNMO) positive electrodes, promise high energy density when coupled with lithium negative electrodes, due to the high discharge voltage platform. However, the intrinsic dissolution of Mn in positive electrode, electrolyte decomposition at high voltage, and dendrite growth on lithium severely compromise cycling stability, limiting the practical application. Herein, we propose ferrocene hexafluorophosphate as an electrolyte additive to achieve dynamic doping of Fe³⁺ in positive electrodes during electrochemical cycling. Furthermore, additive molecule preferentially decomposes at both the positive and negative electrode interfaces, forming thin, dense inorganic positive electrode electrolyte interphase and F, P-rich inorganic solid electrolyte interphase respectively, effectively stabilizing electrode interfaces. Consequently, the Li | |LNMO batteries based on modified electrolytes effectively enhance cycling stability and rate performance at a charge cutoff voltage of 4.9 V and an LNMO pouch cell performs consistently over 160 cycles. Additionally, the efficacy of ferrocene hexafluorophosphate extends beyond LNMO, demonstrating its universal applicability in stabilizing positive electrodes operating at challenging voltages, including LiNi_0.8Co_0.1Mn_0.1O₂, LiNi_0.6Co_0.2Mn_0.2O₂, and LiCoO₂ and a 470 Wh kg⁻¹ level Li metal pouch cell was successfully realized.

We present a simple and scalable surface chemical approach of spraying a dilute DFFSA solution on the Li surface to eliminate the native passivation layer and form a multi-component SEI, enabling stable cycling of a 460 W h kg ⁻¹ Li metal pouch cell.